A standard Holley carb has a 5-1/8" diameter carburetor inlet opening. Dominator inlet is 7 1/4 " so simply purchase a base or filter assembly that is for the Dominator series. BTW... here is a link to Ebay sale of a 14" Dom. filter assembly. You could cut a smaller diameter base to the larger size but the profile of most will not allow this change. Have fun Ron.
http://cgi.ebay.com/ebaymotors/New-H...Q5fAccessories
adding ... the link is for a 14" diameter and remembered you want 11" but the path would be the same and link will get you to correct area.